The class of polymers of carbon monoxide and olefins has been known for some time. U.S. Pat. No. 2,495,286 (Brubaker) discloses such polymers of relatively low carbon monoxide content produced in the presence of free radical initiators, e.g., peroxy compounds. G.B. 1,081,304 discloses similar polymers of higher carbon monoxide content produced in the presence of alkylphosphine complexes of palladium compounds as catalyst. U.S. Pat. No. 3,694,412 (Nozaki) extended the reaction to produce linear alternating polymers in the presence of arylphosphine complexes of palladium moieties and certain inert solvents.
More recently, the class of linear alternating polymers of carbon monoxide and at least one ethylenically unsaturated hydrocarbon, now becoming known as polyketones or polyketone polymers, has become of greater interest. U.S. Pat. No. 4,880,903 (VanBroekhoven et al.) discloses a linear alternating polyketone terpolymer of carbon monoxide, ethylene, and other olefinically unsaturated hydrocarbons, such as propylene. Processes for production of the polyketone polymers typically involve the use of a catalyst composition formed from a compound of a Group VIII metal selected from palladium, cobalt or nickel, the anion of a strong non-hydrohalogenic acid and a bidentate ligand of phosphorus, arsenic or antimony. U.S. Pat. No. 4,843,144 (VanBroekhoven et al.) discloses a process for preparing polymers of carbon monoxide and at least one ethylenically unsaturated hydrocarbon using the preferred catalyst comprising a compound of palladium the anion of a non-hydrohalogenic acid having a pKa of below about 6 and a bidentate ligand of phosphorus.
The resulting polymers are a class of polyketone polymers which possess an attractive set of properties for a variety of applications. The utility of these polymers can be further broadened by selectively blending polyketone polymers with other materials which have complimentary property sets. Most often this is accomplished with polymer blends which are immiscible (heterogeneous) on the molecular scale, yet well dispersed (compatible) on the macroscopic scale.
Immiscible, though compatible, blends are the most common polymer mixture. However, on rare occasions, polymer pairs will form miscible blends. The term miscible will be used herein to describe a mixture of two or more polymers that form a single-phase solution (solid or liquid) on a molecular scale within the amorphous phase. When one or both of the polymer blend components is capable of forming both a crystalline and an amorphous phase, then the term miscible refers only to the amorphous phase in which the separate components are capable of mixing on the molecular level. Miscibility can be achieved by selecting components that interact with one another in an attractive mode (e.g. which mix exothermically).
Several methods can be used to determine miscibility in polymer blends. For example, when a film is prepared from a miscible blend, it is usually optically clear, while immiscible blend films are usually opaque. However, this criterion is not useful when one of the blend components crystallizable. The most commonly used criterion for miscibility is the existence of a single glass transition temperature for a given miscible blend. This parameter is relatively easy to measure for amorphous systems, and rapid if a technique such as differential scanning calorimetry is used. Greater sensitivity, especially useful for semi-crystalline blends, can be obtained when dynamic mechanical methods are employed to measure the glass transition temperature. As the relative proportion of components changes, a smooth change between the glass transition temperatures for the pure blend components and the glass transition temperatures for the various blends will be observed over the miscible range for the blends.
It is an object of this invention to provide a miscible blend of a polyketone polymer and a second polymer.